Organometallics 1994, 13, 808-812
808
Synthesis of Chlorosilanes from (Fluoroalkyl)silanes, Bis(silyl)benzenes, and a,o-Dihydropolysiloxanes Mitsuo I s h i k a w a , * J a Eiji Toyoda,la Michie Ishii,la Atsutaka Yasushi Yamamoto,lb and Masao Y a m a m o t o l c
Kunai,la
Department of Applied Chemistry, Faculty of Engineering, Hiroshima University, Higashi-Hiroshima 724, Silicon-Electronics Materials Research Center, Shin-Etsu Chemical Co.,Ltd., 1-10 Hitomi, Matsuida, Gunma 379-02, and Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya Nishimachi, Nara 630, Japan Received June 29, 199P The reaction of (fluoroalky1)silanes CF3CHZCHzSiMeHz, C ~ F ~ C H Z C H Z S ~ (2a), M ~ Hc81.IZ CHzCHZSiMezH, C8Fl7CH2CH2SiMeHz (3a),and C ~ F ~ ~ C H Z C Hwith Z S ~2Hequiv ~ of CuC12 in the presence of a catalytic amount of CUIin ether gave the respective monochloro(fluoroalky1)silanes selectively. The reaction of 2a and 3a with 4 equiv of CuC12 (CUI)yielded no dichloro derivatives, while treatment of these compounds with CC14 in the presence of a PdClz catalyst gave the respective dichloro compounds. Similar reaction of 1,3-and 1,4-bis(silyl)benzenewith 4 equiv of CuC12 (CUI)afforded 1,3- and 1,4-bis(chlorosilyl)benzenein high yields. The reaction of HMezSi(OSiMez),OSiMezH (n = 0,2, and 3) (8a-10a) with 4 equiv of CuClz (CUI)underwent redistribution to give a series of a,w-dichloropolysiloxanes,ClMezSi(OSiMez),OSiMe&l. Treatment of a,w-dihydropolysiloxanes8a-10a with a catalytic amount of PdClz in refluxing carbon tetrachloride produced the respective a,w-dichloropolysiloxanesin high yields. Introduction Chlorosilanes are useful starting materials for the synthesis of organosilicon compounds including silicon containing polymers. For the synthesis of chlorosilanes, hydrosilanes are often used as the starting compounds. In fact, several methods are available for the synthesis of chlorosilanes from hydrosilanes.2-8 For example, the reaction of hydrosilanes with carbon tetrachloride in the presence of a catalytic amount of palladium chloride affords chlorosilanes in high y i e l d ~ . ~Radical J induced hydrogen-chlorine exchange between hydrosilanes and carbon tetrachloride also produces chlorosilanes in good yields.gJ0 All methods including these two, however, cannot be applied for the selective synthesis of RSiHzCl and RSiHClz from RSiH3, and RzSiHCl from RzSiHz. Recently, we have found that the reaction of RSiH3 and RzSiHz with 2 equiv of CuClz in the presence of a catalytic amount of CUIin ether affords selectively RSiHzCl and RzSiHCl in high yields, while the reaction of RSiH3 with 4 equiv of CuClz (CUI)produces RSiHClZ in high yield.11 Cunico and Dexheimer have reported that the reaction of hydrosilanes and CuC12 in acetonitrile produces chloAbstract published in Advance ACS Abstracts, February 1, 1994. (1)(a) Hiroshima University. (b) Shin-Etau Chemical Co. Ltd. (c) Nara Women's University. (2) Whitmore, F. C.; Pietrusza, E.; Sommer, L. H. J.Am. Chem. SOC. 1947,69,2108. (3) Jenkins, J. W.; Post, H. W. J. Org. Chem. 1960, 15, 556. (4) Russel, G. A. J. Org. Chem. 1966, 21, 1190. (5) Curtice, J.; Gillman, H.; Hammond, G. S.J.Am. Chem. SOC.1967, 79, 4154. (6)Nagai,Y.; Yamazaki, K.; Shiojima, I.; Kobori, N.; Hayashi, M. J. Organomet. Chem. 1967, 9, P21. (7) Nagai, Y.; Mataumoto, H.; Yagihara, T.; Morishita, K. Kogyo Kagaku Zasshi 1968, 71,112. (8)Cunico, R. F.; Dexheimer, E. M. Synth. React. Inorg. Metal-Org. Chem. 1974, 4 (l), 23. (9) Sakurai, H.; Murakami, M.; Kumada, M. J.Am. Chem. SOC.1969, 91, 519. (10) Jung, I. N.; Weber, W. P. J. Org. Chem. 1976,41, 946. (11)Kunai, A.; Kawakami, T.; Toyoda, E.; Ishikawa, M. Organometallics 1992, 11, 2708. 0
rosilanes in high yields.8 In ether solution, however, treatment of hydrosilanes with CuClz in the absence of a CUI catalyst gives no chlorosilanes, but the starting materials are recovered unchanged. In this paper we report the synthesis of chlorosilanes which can be used as the starting compounds for the useful industrial materials, using the CuClz-CUI method. Results and Discussion (Fluoroalkyl)silanes.'2 When a mixture of (fluoroalky1)methylsilane RfCH&HzSi(R)Hz (la, Rf = CF3, R = Me) and 2 equiv of CuC12 in the presence of a catalytic amount of CUI in diethyl ether was stirred at room temperature for 33 h, the reaction proceeded cleanly to give chloro(fluoroalky1)methylsilane (lb). Distillation of the resulting mixture after filtration of inorganic solids ! isolated under a dry nitrogen atmosphere gave l b in 57 % yield (Scheme 1). Scheme 1
+
R,CH,CH,Si(R)H, 2CuC1, la, R, = CF,, R = Me 2a, R, = C4Fg,R = Me 3a, R, = C8FI7,R = Me 4a, R, = C8F1,, R = H
CUI
R,CH,CH,Si(R)HCl lb, R, = CF,, R = Me 2b, R, = C,Fg, R = Me 3b, R, = C8F1,, R = Me 4b, R, = C8F17, R = H Although compound la was completely converted to l b after a 33-h reaction at room temperature, it was found that the longer reaction time was necessary for complete transformation of 2a-4a into products 2b-4b. Thus, when (12) All starting fluoroalkylsilanes were supplied from Shin-Etau Chimical Co., Ltd.
Q276-7333/94/2313-Q8Q8$Q4.5Q/Q0 1994 American Chemical Society
Synthesis of Chlorosilanes
Organometallics, VoE. 13, No. 3,1994 809
l " " 1 " " l ' " ' " ~ ' ~ 1 ' ' ' " " ' " " ' ' " ' ' " " ' ' ~ ' ' ' ' ~ 7 6 5 4 3 2
n
m 1
0
-1
Figure 1. lH NMR spectrum of Zb in C6D6. 2a (Rf = CdFg, R = Me) was treated with 2 equiv of CuCl2 (CUI)under the same conditions for 11h, only 29% of 2a was consumed to give the chlorosilane 2b. However, the reaction of 2a with CuClz (CUI)for 71 h led to approximately 100% conversion of 2a, giving 2b in 87% yield
(GLC yield).l3 Fractional distillation of the mixture after filtration of the resulting inorganic salts afforded 2b in 49 % isolated yield. Similar treatment of 3a (Rf = C8F17, R = Me) with CuC12 (CUI)for 69 h produced 3b in 91% yield (GLC yield). Distillation of the mixture gave 3b in 60% isolated yield. (Fluoroalky1)silane 4a (Rf = c817, R = H) also reacted with CuC12 (CUI)for 69 h to give 4b in 65 75 isolated yield. In all reactions, no other products were detected in the reaction mixture by 'H and 13CNMR spectrometric analysis. A change in reaction temperature brought about a considerable reduction in time. Thus, the reaction of 2a with 2 equiv of CuC12 (CUI)at refluxing temperature for 9 h produced 2b in 76 5% GLC yield, while 4a for 10 h gave 4b in 94% GLC yield. Products lb-4b are very sensitive to moisture and are readily hydrolyzed in air to produce siloxanes. Consequently, when the reaction mixture is analyzed by GLC, small amounts of siloxanes are always detected. However, the products isolated by distillation involve no siloxanes, as indicated by 'H and 13CNMR spectrometric analysis. The 1H NMR spectrum of 2b obtained from distillation is shown in Figure 1, as a typical example. Previously, we reported that the reaction of PhSiH3 with 4 equiv of CuCl2 (CUI)gave dichlorophenylsilane in high yield. A similar reaction of 4a with 4 equiv of CuC12 (CUI),however, afforded no dichlorosilyl derivative. Again, monochloro compound 4b was obtained as the sole product. As expected, (fluoroalky1)dimethylsilanecould be readily converted to the corresponding chlorosilane. Thus, treatment of C817CH2CHzSiMe2H (5a) with 2 equiv of CuCl2 (CUI) in ether at room temperature for 57 h gave (13) In the GLC analysisof the reactionmixtures,siloxaneswere always produced in 6-10% yields in handling the mixture: and therefore we calculated the yields of chlorosilanes using the s u m of the peaks for siloxanes and chlorosilanes.
CaF17CH2CHzSiMe2Cl (5b)14in 67 % isolated yield. The CuClz (CUI)method affords no dichlorosilyl derivatives from fluoroalkylsilanesdescribed here. However,we found that the palladium-catalyzed Si-H/C-Cl exchange reaction can be used for the preparation of dichloro(fluoroalky1)~i1anes.l~ Thus, treatment of 2a with a catalytic amount of PdCl2 in refluxing carbon tetrachloride for 67 h gave C4FgCH2CH2SiMeC12 (213) in 61% yield, while a similar reaction of 3a with carbon tetrachloride produced c8F17' CH2CH2SiMeC12 (3c) in 84% yield. Mass Spectrometric Analysis for Chloro(fluoroalky1)silanes. The combustion elemental analysis for
chloro(fluoroalky1)silanes reported here is not in accord with their theoretical values. Carbon contents for all chloro(fluoroalky1)silanesare always determined as the value higher than their calculated ones. Therefore, we carried out mass spectrometric analysis for these compounds. The mass spectrum for l b clearly shows its molecular ion, while all compounds having a C4FgCHzCH2 and CsF17CH2CH2 group reveal no molecular ions. Mass spectra for 2b, 2c, 3b, 3c, and 5b, which have both a methyl group and chlorine on the silicon atom revealed the presence of the ions corresponding to [M - CH31+ as the highest mass fragment. Compound 4b that has no methyl group on the silicon atom, however, showed neither a molecular ion nor the ion corresponding to [M - CH31+, but an ion at mlz 409 (CloF15H4+) was detected as the highest mass fragment. Interestingly, mass spectra for 2b and 2c revealed an ion at mlz 209 (CsF,H4+),in addition to [M - CHsl+ ions, and the respective silyl cations, Cl(Me)HSi+ for 2b and Clz(Me)Si+for 2c, as important fragments. Similarly, the ion at mlz 409 (CloF15H4+)and the respective silyl cations were observed in their fragments for 3b, 3c, and 5b. The fragment ions at mlz 209 and 409 were also detected as the largest fragments, in the mass spectra for the starting compounds 2a-Sa. Again, neither molecular ions nor [M - CH3]+ ions were detected for 2a-5a. Moreover, both of (14) Berendsen, G.E.;Pikaart, K. A.; De Galan, L. Anal. Chem. 1980, 52,1990. (15) Owen, M. J.; Groh, J. L. J. Appl. Polym. Sci. 1990, 40, 789.
Zshikawa et al.
810 Organometallics, Vol. 13, No. 3, 1994 Scheme 2 [F(CF2),CHzCH~SiR'R2R3] * +
1
F I
-SiF2RZR3
Cll9 with n = 0 (15% yield), n = 1 (23%), n = 2 (24%), n = 3 (lo%), n = 4 (6%), and n = 5-11 (less than 5%). In early stages of the reaction, a-chloro-o-hydropolysiloxanes were observed in the reaction mixture. After 43 h of reaction, however,all of a-chloro-o-hydropolysiloxanes were transformed into a,o-dichloropolysiloxanes.Lower homologs of ClMezSi(OSiMez),,OSiMezClwith n = 0 and n = 1were isolated by fractional distillation of the resulting mixture, and their structures were verified by spectrometric analysis. The structures of a,w-dichloropolysiloxanes with n = 2 and 3 were confirmed by comparison of their GLC retention times with those of authentic samples, as well as by GC-mass spectrometric analysis. Higher homologs with n = 4-11 were identified by GC-mass spectrometric analysis of the mixture (Scheme 4).
Scheme 4
-
HMe2Si(OSiMe2),,0SiMe2H 4cuc1z(cuI) 8a,n = 0 9a, n = 2 loa, n = 3
C1Me2Si(OSiMe2),,0SiMe2Cl
Scheme 3 H,Si-@SiH3
6a, 1,3-isomer 7a, 1,4-isomer
+
4 CuC12(CuI)
-
SiH,Cl
ClH2Si-@
6b, 1.3-isomer 7b, 1.4-isomer
the starting compounds and products revealed the presence of a fragment ion at mlz 59 (CsH4F+). The compositions of ions mlz 409, 209, and 59 were confirmed by high resolution mass spectrometry (see Experimental Section). We suggest the fragmentation pattern leading to important ions from the initially formed radical cation as shown in Scheme 2. Bis(sily1)benzene. This method can also be used for selective synthesis of bis(chlorosily1)benzenes from bis(sily1)benzenes. Thus, the reaction of 1,3-bis(silyl)benzene ( 6 a P with 4 equiv of CuClz (CUI) in ether at room temperature afforded 1,3-bis(chlorosilyl)benzene (6b) in 54% isolated yield (Scheme 3). A similar reaction of 1,4-bis(silyl)benzene (7a)" under the same conditions produced 1,4-bis(chlorosilyl)benzene (7b) in 61% yield. The reactions proceeded cleanly to give bis(chlorosily1)benzenes 6b and 7b, and no other products were detected by GLC analysis. Products 6b and 7b are highly sensitive to moisture, but they can be readily isolated by distillation from the reaction mixture. a,w-Dihydropolysiloxanes.We attempted to prepare a,wdichloropolysiloxe oligomersfrom the corresponding a,w-dihydropolysiloxanes. In all cases, not only the transformation of Si-H bonds to Si-C1 bonds but also redistribution reaction to give a series of a,o-dichloropolysiloxane oligomers was observed. Thus, the reaction of 1,1,3,3-tetramethyldisiloxane(8a)lswith 4 equiv of CuCl2 (CUI)in ether a t room temperature for 43 h afforded a mixture consistingof a seriesof ClMezSi(OSiMe&,OSiMe2(16) Woo,H.-G.; Walzer, J. F.;Tilley, T. D. Macromolecules 1991,24, 6863. (17) Anderson, D. R.; Holovka, J. M. J. Chem. SOC.1965, 2269. (18) Ohkawara,R.; Sakiyama,M. Bull. Chem. SOC.Jpn. 1966,29,236.
The reaction of 1,7-dihydrooctamethyltetrasiloxane (9a)20with 4 equiv of CuC12 (CUI)in refluxing ether for 32 h resulted in the redistribution giving a homologous series of ClMe2Si(OSiMe2).OSiMe&l with n = 0 (5% yield), n = 1 (32%),n = 2 (23%),n = 3 (7%), n = 4 (5%), and n = 5-11 (less than 5%). Treatment of 1,g-dihydrodecamethylpentasiloxe (loa)with4 equiv of CuClz (CUI) in ether at room temperature for 125h gave aresult similar to that of 9a. A series of a,o-dichloropolysiloxanesClMer Si(OSiMe2).OSiMe2Clwith n = 1(1%yield), n = 2 (5%), n = 3 (19%),n = 4 (12%),n = 5 (5%),and n = 6-12 (less than 3%), arising from the redistribution, and the hydrogen-chlorine exchange reaction was obtained. In this reaction, a,w-dihydropolysiloxaneswith n = 1 (2%), n = 2 (20%),n = 3 (starting compound, 18%),and n = 4 (3%) were also detected. Interestingly, the reaction of 8a with 4 equiv of CuCl2 (CUI)in the presence of a 10-fold excess of hexamethyldisiloxane in refluxing ether for 20 h afforded a series of permethylated polysiloxanes, MesSi(OSiMez).OSiMes with n = 119 (41% yield), n = 21g (24%), n = 319 (23%), n = 419 (6%),and n = 5-821 (less than 3%) (Scheme 5). In this reaction, chloropentamethyldisiloxanewas detected by GC-mass spectrometric analysis, but no a,@-dichloropolysiloxanes were detected in the reaction mixture. Careful analysis of the reaction mixture by GC-mass spectrometric analysisindicated that chlorotrimethylailane was also produced. The same results were obtained when a,o-dihydropolysiloxane 9a was treated with 4 equiv of CuC12 (CUI) in the presence of a 10-fold excess of hexamethyldisiloxane in refluxing ether for 95 h. In this reaction, a series of Me$3(OSiMez).OSiMes with n = 1 (45% yield), n = 2 (25%),n = 3 (21%),n = 4 (6%), and n = 5-7 (less than 1%) was formed. The present redistribution reaction is observed only for compounds which have an Si-H bond. In fact, treatment of decamethyltetrasiloxane with 4 equiv of CuClz (CUI)in refluxing ether for 40 h afforded no products derived from the redistribution reaction, but the starting permethylated polysiloxane was recovered unchanged. The reaction of 1,3-dichlorotetramethyldisiloxanewith 4 equiv of CuClz (19) Patnode, W. 1.; Wilcock, 0. F. J. Am. Chem. SOC.1946,68,358. (20) Ohkawara,R.; Sakiyama,M. Bull. Chem. SOC. Jpn. 1956,29,647. (21) Wilcock, D. E. J. Am. Chem. SOC.1946,68,691.
Organometallics, Vol. 13, No.3, 1994 811
Synthesis of Chlorosilanes
(CUI)under the same conditionsyielded no products, again the starting dichlorotetramethyldisiloxanewas recovered quantitatively.
+ 10Me,SiOSiMe3
-
+
Me,SiOSie,
-
4cuc12 (CUI)
Me,Si(OSiMe,),OSiMe,
Et,SiH
cUc1z(cUI),
[
Et$;
-H
Me3SiO-
Scheme 5 8a or Sa
Scheme 6
Et,Si-0-SiMe,
+ Me,SiCl
Interestingly, when a mixture of triethylsilane and a large excess of hexamethyldisiloxanewas heated toreflux in the presence of 2 equiv of CuC12 (CUI)in ether for 60 h, l,l,l-triethyltrimethyldisiloxane22 was obtained in 71 % yield, in addition to an 8%yield of ~hlorotriethylsilane.~3 Chlorotrimethylsilane was also detected in the resulting mixture by GC-mass spectrometricanalysis. These resulta clearly indicate that the hydrogen-trimethylsiloxy exchange between triethylsilane and hexamethyldisiloxane occurs (Scheme 6). A detailed mechanism for redistribution of a,w-dihydropolysiloxanesis still unknown, but presumably the reaction proceeds with exchange of hydrogen with a siloxy group, as observed in the reaction of triethylsilane and hexamethyldisiloxane. By using the palladium dichloride-catalyzed Si-H/CC1 exchange reaction, a,w-dihydropolysiloxanescan be readily transformedinto a,w-dichloropolysiloxanes.When tetramethyldisiloxane 8a was heated to reflux in carbon tetrachloride in the presence of a palladium dichloride catalyst, the reaction proceeded cleanly to produce 1,3dichlorotetramethyldisiloxane (8b)lg in 82 % yield. No other products were observed in the reaction mixture. Similar treatment of Sa and 10a with carbon tetrachloride in the presence of the palladium catalyst afforded 1,7dichlorooctamethyltetrasiloxane(9b)19 and 1,9-dichlorodecamethylpentasiloxane(10b)19in 77% and 72% yields, respectively. In conclusion, the reaction of fluoroalkyl-substituted silanes with CuClz (CUI) gave selectively monochloro(fluoroalky1)silanes. Similar reaction of 1,3- and 1,4-bis(sily1)benzene affords the respective bis(chlorosily1)benzene as the sole product, while a,dihyd.ropolysiloxanes undergo redistribution and also the hydrogen-chlorine exchange reaction to give a homologous series of a,wdichloropolysiloxanes. Experimental Section General Procedure. Diethylether used as asolvent was dried over sodium benzophenone-ketyl and distilled just before use. Copper salts, CuCl2 and CUI,used for all reactions were dried at 100 OC under reduced pressure for 8 h just before use. 'H, 13C, and W i NMR spectra were recorded on JEOL Model JNM-EX 270 and Bruker AM-X 400 spectrometers. IR spectra were measured on a Perkin-Elmer 1600-FT infrared spectrometer. Low-resolution mass spectra were measured on a SimadzuModel QP-1000 instrument. High-resolution mass spectra were measured on a Hitachi M-80B mass spectrometer. All reactionsof fluoroalkylsilaneswith CuClz(CuI)were carried out at room temperature under an atmosphere of dry nitrogen, and the products were separated from the reaction mixture by distillation after filtration of the mixture to remove inorganic salts. The redistribution reaction of a,w-dihydropolysiloxanes was monitored by GLC, and the yields of the products were determined by GLC using tridecane as an internal standard. (22)Aimworth, C.;Kuo, Yu-Neng,J. Organomet. Chem. 1972,46 fl), 73. (23)Voronkov, M. G.Izu. Akad. Nauk SSSR, Otdel. Khim. Nauk 1987,517.
+
]
SiMe,
Me,SM
1
CUClz(CuI)
Me,SiCl
Preparation of Chloro(3,3,3-trifluoropropyl)methylsilane (lb). A mixture of 10.1 g (71.0 mmol) of CFsCHzCHaSiMeHz, 19.1g (142.1 mmol) of anhydrous CuClZ, and 0.725 g (3.81 "01) of anhydrous CUI in 250 mL of ether was stirred at room temperature for 33 h. The resulting mixture wan fitered to remove copper salts. Fractionaldistillation of the fiitrate afforded 7.1 g (57% yield) of CFsCHzCHzSiMeHCk bp 98-100 OC; 1H NMR (6, in CDCl3) 0.54 (6,3H, MeSi, J = 3.1 Hz),1.10-1.15 (m, 2H, CFsCH&H&i), 2.16-2.21 (m, 2H, CFgCH&H2Si), 4.84 (br m, lH, HSi); W NMR (6, in CDCls) -0.76 (MeSi), 9.15 (CFsCH2CHfii), 28.03 (q, CF&H&H&i, JCF = 30.6 Hz), 127.21 (9, JCF = 276.3 Hz); MS m/z 176 (M+), 161 ([M - CHa]+), 79 (HClMeSi+),59 (C3H4F+);IR 2967, 2136 cm-l; exact mass calcd for C,H&lFsSi 176.0035, found 176.0018. Preparation of Chloro( 3,3,4,4,5,5,6,6,6-nonafluorohexyl)methylsilane (2b). A mixture of 9.96 g (34.1 mmol) of CPgCH&HzSiMeH2,9.28 g (69.0 mmol) of CuClz, and 0.347 g (1.82 mmol) of CUI in 200 mL of ether was stirred at room temperature for 71 h. The resulting mixture was filtered to remove copper salts and distilled fractionally to give 5.50 g (49% yield) of C$'&HzCH2SiMeHC1: bp 146-148 OC; lH NMR (6, in CDCb) 0.56(d,3H,MeSi, J =3.0Hz), 1.11-1.19 (m,2H,CIF&H2CHfii), 2.11-2.27 (m, 2H, C,F&H&HZSi), 4.82-4.90 (br m, lH, HSi);13C NMR (6, in CDCb) -0.73 (MeSi),7.03 (C~SCH~CHBS~), 25.15 (t, Cfl&H&Hfii,&F = 23.8 Hz), 104.51-123.76 (m, C,F& 'H NMR (6, in c a s ) 0.13 (d, 3H, MeSi, J = 3.3 Hz), 0.75-0.82 (m, 2H, C,FgCHzCHfii), 1.91-2.04 (m, 2H, CPgCH&H2Si), 4.55-4.62 (br m, lH, HSi); lacNMR (6, in c a s ) -1.34 (MeSi), 7.05 (C,Fg= 23.8 Hz), 105.5-125.0 CHaCHfii), 25.34 (t,C,FgCH&H2Si, JCF (m, Cze); MS mlz 311 ([M - CHsl+), 209 (Cst4F7+), 79 (HClMeSi+),59 (CsH,F+);IR 2966,2172 (Si-H), 1220,885cm-1; exact mass calcd for C&&lF&i ([M - Me]+) 310.9704, found 310.9664. Preparation of Chloro(3,3,4,4,5,5,6,6,7,7,8,8,S,S,lO,lO,lOheptadecafluorodecy1)methylsilane(3b). A mixture of 9.99 of g (20.3 mmol) of CsF&HzCH2SiMeH2, 5.53 g (41.1 "01) CuClZ, and 0.200 g (1.05 mmol) of CUI in 200 mL of ether was stirred at room temperature for 69 h. The resulting mixture was filtered, and the filtrate was concentrated. The residue was then distilled under reduced pressure to give 6.42 g (61% yield) of C817CH2CH2SiMeHC1: bp 104-107 OC (20 mmHg); 1H NMR (6, in CDCls) 0.56 (d, 3H, MeSi, J = 3.0 Hz), 1.11-1.20 (m, 2H, C$&H&H&i), 2.10-2.30 (m, 2H, Ca&H&Hai), 4.80-4.90 (br m, lH, HSi); 13CNMR (6, in CDCb)-0.73 (MeSi),7.08 (C$17= 23.8 Hz), 106.29CH2CH&i), 25.26 (t, Ca17CH&H2Si, JCF 121.89 (m, c817); MS m/z 511 ([M - CHsl+), 409 (CloH91~+), 79 (HClMeSi+),59 (CsHIF+);IR 2967,2172 (HSi), 1205,887,842 cm-l; exact mass calcd for C1~H5ClF17Si([M - Me]+) 510.9576, found 510.9669. Preparation of Chloro(3,3,4,4,5,5,6,6,7,7,8,8,S,S,lO,lO,lOheptadecafluorodecy1)silane(4b). A mixture of 10.04g (21.0 5.73 g (42.63 mmol) of CuClz, and mmol) of CsF1~CH2CH2SiHs, 0.208 g (1.09 mmol) of CUI in 160 mL of ether was stirred at room temperature for 69 h. The resulting mixture was filtered, and the filtrate was distilled under reduced pressure to give 6.99 g (65% yield) of C ~ I . I C H ~ C H Z S ~ Hbp ZC 94-96 ~ : "C (21 mmHg); lH NMR (6, in CDCb) 1.24-1.32 (m, 2H, C$&HzCHfii), 2.122.35 (m, 2H, C817CH&HzSi), 4.76-4.80 (br m, 2H, HSi); 1% NMR (6, in CDC&J 4.53 (CsFl&HzCHfii), 25.41 (t,C~I~CHPCHZSi,JCF = 23.2 Hz), 104.19-123.56 (m, C817); mlz 409 (Cl&Fls+), 65 (HzCISi+),59 (CsHZ+); IR 2949, 2166 (HSi), 1204,869,658 cm-1; exact mass calcd for Cl&Fls 409.0073, found 409.0084.
812 Organometallics, Vol. 13, No. 3, 1994
Reaction of 2a with 2 equiv of CuClz at Refluxing Temperature. A mixture of 0.950 g (3.25 mmol) of 2a, 0.920 g (6.84 mmol) of CuC12, and 25 mg (0.13 mmol) of CUIin 15 mL of ether was heated to reflux, and the reaction was monitored by GLC. After 9 h of reaction, chlorosilane 2b was formed in 76% GLC yield. Reaction of 4a with 2 equiv of CuClt at Refluxing Temperature. A mixture of 1.050 g (2.20 mmol) of 4a, 0.679 g (5.05 mmol) of CuCl2, and 20 mg (0.11 mmol) of CUI in 15 mL of ether was heated to reflux for 10 h. The mixture was analyzed by GLC as being chlorosilane 4b 94% GLC yield. Reaction of 4a with 4 equiv of CuCla in the Presence of a Catalytic Amount of CUI. A mixture of 9.99 g (20.9 mmol) of 4a, 11.40 g (84.8 mmol) of CuCl2, and 0.209 g (1.10 mmol) of CUIin 300 mL of ether was stirred at room temperature for 189 h. The resulting mixture was filtered, and the filtrate was distilled under reduced pressure t o give 4.71 g (32% yield) of C ~ I ~ C H ~ C H ~ bp ~ ~87-90 H ~ "C C I(15 : mmHg). All spectral data of the product were identical with those of an authentic sample. Preparation of Chloro(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10heptadecafluorodecy1)dimethylsilane (5b). Into a 300-mL flask fitted with a condenser was placed a mixture of 8.85 g (17.5 mmol) of C$&H&H2SiMe2H, 4.97 g (37.0 mmol) of CuC12,and 64 mg (0.34 mmol) of CUIin 150 mL of ether. The mixture was stirred by a magnetic stirrer at room temperature for 57 h. The resulting mixture was filtered and the filtrate was fractionally distilled under reduced pressure to give 6.35 g (67% yield) of C817CH2CH2SiMezCI: bp 103-104 "C (12 mmHg); 1H NMR (6, in CDC&) 0.47 (8, 6H, MezSi), 1.00-1.12 (m, 2H, CHzCHpSi), 2.05-2.27 (m, 2H, CH&HzSi); 1% NMR (6, in CDCl3) 1.26 (MezSi), 8.63 (CH&HpSi), 25.23 (t,CHzCH2Si,JCF= 23.8 Hz), 106.25122.41 (m, C$d; MS mlz 525 ([M - CHsl+), 409 (CloH$l~+), 93 (MezClSi+),59 (C3H$+); IR 2969,2908,1205,1070,900,851 cm-l; exact mass calcd for C11H,ClF17Si ([M - Me]+) 524.9733, found 524.9630;calcd for Cl&F17409.0072,found 409.0058; calcd for C3H$ 59.0297, found 59.0314. Preparation of Dichloro(3,3,4,4,5,5,6,6,6-nonafluorohexy1)methylsilane(2c). A solution of 4.78 g (16.1 mmol) of C$gCHaCHzSiMeH2 and ca. 10 mg (0.056 mmol) of palladium dichloride in 50 mL of carbon tetrachloride was refluxed for 60 h. The solvent was evaporated, and the residue was distilled to give 3.54 g (61% yield) of C$&H&H2SiMeCl2: bp 163-164 "C; 1H NMR (6, in CDCq) 0.85 (8, 3H, MeSi), 1.32-1.38 (m, 2H, CIFBCH~CH~S~), 2.16-2.35 (m, 2H, C$BCHZCH&~); lSC NMR (6, in CDCh) 4.73 (MeSi), 11.57 (Cd&HZCHpSi), 24.64 (t, C$~C&CH&,JCF 23.2 Hz), 107.99-121.72 (m, c$g); MS m/z 345 ([M - Me]+), 209 (CeH$7+), 113 (ClzMeSi+),59 (CsH$+); IR 2910,1221,880 cm-l; exact mass calcd for C&ClzF&i ([M - CHs]+) 344.9314, found 344.9309. Preparationof Dichloro(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10heptadecafluorodecy1)methylsilane(3c). A solution of 5.327 g (10.822 mmol) of C817CH2CH2SiMeHz and ca. 10 mg (0.056 mmol) of palladium dichloride in 50 mL of carbon tetrachloride was refluxed for 61 h. The solventwas evaporated, and the residue was distilled under reduced pressure to give 5.05 g (84% yield) of C$&H&H2SiMeClz: bp 113-114 "C (16 mmHg); lH NMR (6, in CDCls) 0.85 (8, 3H, MeSi), 1.32-1.38 (m, 2H, C817CHZCHdi), 2.16-2.29 (m, 2H, C817CH&HzSi); lacNMR (6, in CDCl3) 4.89 (MeSi), 11.70 (C$17CH&Hfii), 24.80 (t, C ~ ~ ~ C H Z CJCF H ~=S23.2 ~ , Hz) 105.55-120.45 (m, C817); MS mlz 545 ([M - CHs]+), 409 (C&$16+), 113 (ClzMeSi+), 59 (C3H$+); IR 2954,2912, 1204, 897, 741 cm-l; exact mass calcd for C I I H ~ C ~ F([M I~S ~ - C1]+) 524.9732, found 524.9604; calcd for CsH$ 59.0297, found 59.0319. Preparation of l,3-Bis(chlorosilyl)benzene(6b). Into a 300-mL flask fitted with a condenser was placed a mixture of 6.5 g (47 mmol) of 1,3-bis(silyl)benzene(6a), 25.3 g (190 mmol) of of CUI in 105 mL of ether. The CuCl2, and 0.455 g (2.4 "01) mixture was stirred with a magnetic stirrer at room temperature for 39 h. The resulting mixture was filtered, and the filtrate was distilled under reduced pressure to give 5.3 g (54% yield) of 6b: bp 135-136 "C (62 mmHg); lH NMR (6, in c&) 4.96 ( 8 , 4H, H-Si), 6.92 (t, lH, ring proton ((251, J = 7.26 Hz),7.33 (dd, 2H,
Ishikawa et al. ring protons (C4,6), J = 1.32, J = 7.26 Hz), 7.64 (br t, lH, ring proton ((22); lSCNMR (6, in c a s ) 128.4,130.7 ,137.3,140.0; MS mlz 206 (M+);IR 3072,2183,1578,1373,936,852 cm-l; exact mass calcd for C&$&Siz 205.9542, found 205.9527. Preparation of 1,4-Bis(chlorosilyl)benzene(7b). Into a 200-mL flask fitted with a condenser was placed a mixture of 6.0 g (43 mmol) of 1,4-bis(silyl)benzene(?a), 23.6 g (180 mmol) of CuC12, and 0.403 g (2.1 mmol) of CUI in 90 mL of ether. The mixture was stirred at room temperature for 18h. The resulting mixture was filtered and the filtrate was distilled under reduced pressure to give 5.4 g (61% yield) of 7b: bp 140 "C (71 mmHg); lH NMR (6, in C&S) 4.97 (s,4H,H-Si), 7.25 (s,4H, ring protons); 13CNMR (6, in CDCh) 133.7,134.1; MS mlz 206 ( M + ) ;IR 3055, 2183,1136,935,846 cm-l. Anal. Calcd for C&Cl2Si$ C, 34.78; H, 3.89. Found: C, 34.58; H, 3.88.
Preparation of 1,3-Dichlorotetramethyldisiloxane(8b). A solution of 10.5g (78.1 mmol) of 8a and ca. 10 mg (0.056 mmol) of palladium dichloride in 100 mL of carbon tetrachloride was stirred at room temperature for 44 h. Fractional distillation of the reaction mixture afforded 12.957 g (82% yield) of 8b19 bp 135-137 "C; lH NMR (6, in CDCl3) 0.49 (s,12H, MeSi); 19CNMR (6, in CDClS) 3.92 (MeSi); MS mlz 187 ([M - CHsl+), 167 ([M - Cl]+); IR 2969, 1403, 1262, 1078 (Si-0-Si) 808,676 cm-1.
Preparationof 1,7-Dichlor~tamethyltetrasiloxane (9b). A solution of 10.1 g (35.7 mmol) of 9a and ca. 10 mg (0.056 mmol) of palladium dichloride in 50 mL of carbon tetrachloride was stirred at room temperature for 21 h. The solventwas evaporated, and the residue was distilled under reduced pressure to give 9.7 g (77% yield) of 9b:lgbp 112-114 "C (20 mmHg); lH NMR (6, in CDC&)0.14 (8, 12H, MeSi), 0.45 (8, 12H, MeSi); l3C NMR (6, in CDCla) 0.78,4.05 (MeSi); MS m/z 335 ([M- CHsl+),315 ([M - Cl]+); IR 2965,1411, 1263, 1044 (Si-0-Si) 804 cm-l.
Preparation of 1,9-Dichlorodecamethylpentasiloxane (lob). A solution of 8.34 g (23.4 mmol) of loa and ca. 10 mg (0.056 mmol) of palladium dichloride in 100 mL of carbon tetrachloride was stirred at room temperature for 70 h. The solvent was evaporated, and the residue was distilled under reduced pressure to give 7.19 g (72% yield) of lob? bp 70-72 "C (1mmHg); lH NMR (6, in CDCl3) 0.09 (s,6H, MeSi), 0.13 (8, 12H, MeSi), 0.44 (8, 12H, MeSi); lSC NMR (6, in CDCl3) 0.83, 0.94, 4.03 (MeSi); MS mlz 409 ([M - CHsI+),389 ([M - ClI+); IR 2964, 1412, 1261, 1033 (Si-0-Si), 793 cm-l. Reaction of 1,1,3,3-Tetramethyldisiloxane(8a) with 4 equiv of CuClz (CUI). A mixture of 14.76 g (110 mmol) of 8a, 61.51 g (457 mmol) of CuC12, and 1.096 g (5.75 mmol) of CUIin 300 mL of ether was stirred at room temperature. The redistribution reaction was monitored by GLC. After 124 h, the resulting mixture was filtered and the filtrate was fractionally distilled to give 2.64 g (12% yield) of 1,3-dichlorotetramethyldisiloxane (8b) and 4.78 g (16% yield) of 1,Bdichlorohexamethyltrisiloxane. For 8b: bp 138-139 "C; All spectral data of 8b were identical with those of an authentic sample. For 1,5-dichlorohexamethyltrisiloxane:bp 183-189 "C; 1H NMR (6, in CDCls) 0.16 (8, 6H, MeSi), 0.45 (8, 12H, MeSi); l3C NMR (6, in CDCla) 0.76,4.01 (MeSi);MS mlt 261 ([M - CHsI+);IR 2963, 1411, 1261, 1090 (Si-0-Si), 801 cm-l. Acknowledgment. This research was supported in part by a Grant-in-Aid for Scientific Research on Priority Area of Organic Unusual Valency, No. 04217103, from the Ministry of Education, Science, and Culture. We also express our appreciation t o Shin-Etsu Chemical Co. Ltd., Nitto Electric Industrial Co. Ltd., Dow Corning Asia Ltd., Toshiba Silicone Co. Ltd., Sumitomo Electric Industry, Kaneka Corp., and t h e Japan High Polymer Center for financial support. Supplementary Material Available: Figures of lH NMR spectra of lb, 3b, 4b, 5b, 2c, 3c, and 6c, which were isolated by distillation (7 pages). Ordering information is given on any current masthead page. OM9304391
